For many years, the lithographic and offset printing industry has been plagued with the problem of keeping the polished surface of printing cylinders clean and free of corrosion of any kind, such problems arising so frequently that costly and time consuming press shutdown is necessary mainly to clean the cylinders and replace the deteriorated packing papers of the makeready in order to maintain the necessary high quality of the printed product.
Even spraying the cylinder with materials that would prevent spoiling of the polished cylinder or plate surface has been insufficient and for the past twenty or more years, various improvements have been make in the tympan or packing papers and makeready construction for this purpose, especially in the character and quality of the packing papers employed. To the present time, however, none has solved the problem of effectively preventing corrosion of the printing cylinder surfaces, particularly in the areas adjacent the ends of the cylinders which are exposed to the ambient environment, and it is the object of the present invention to provide a means for overcoming that problem.